Recently, a novel form of long-term sensorimotor adaptation, termed long term frequency elevation (LTFE) has been identified in the weakly electric fish (Oestreich & Zakon, 2002). The site of this sensorimotor adaptation is the pacemaker nucleus (PMn), the premotor network responsible for controlling the electric organ discharge (EOD) frequency. Shifts in the PMn firing frequency arise from the activation of different afferent glutamatergic inputs. While it has been well established that ionotropic glutamate receptors mediate shifts in PMn firing frequency, the role of metabotropic glutamate receptors (mGluRs) remains unexplored. We propose several studies in order to explore the role of mGluRs in the PMn and whether they contribute to the generation of LTFE: (1) use immunocytological techniques to map the distribution of different mGluRs in the PMn, (2) use various mGluR agonists and antagonists in the PMn slice preparation to determine which mGluRs contribute to LTFE in vitro, and (3) use in vivo pharmacology and recordings to examine which mGluRs contribute to LTFE in the intact animal.